Device to support and swing the hearth in an electric furnace

Abstract

Device to support and swing the hearth in an electric furnace, whether it be the type operating on direct or alternate current, the furnace being able to be of the channel type, EBT with the hearth lowered or not, OBT or other type, the hearth (11) cooperating at the upper part with a cooled side wall (12) having a closure system (14) which can be temporally associated, the hearth (11) being supported by a platform (18), the device comprising a plurality of lifting cylinders (19, 119) associated at the lower part with the platform (18) and at least a translation and/or oscillation actuator (20, 120; 32) associated at the side of the platform (18), the lifting (19, 119) and translation (20, 120; 32) cylinders being able to be driven independently and in a correlated manner so as to obtain on the hearth (11) desired movements of lifting, translation, swinging, oscillation or a combination of such movements.

We claim: 
     
       1. A device to support and swing a hearth in an electric furnace, an upper part of the hearth (11) being configured to cooperate in temporary association with a cooled side wall (12) and with a closure system (14), comprising: a platform (18) for supporting the hearth (11), a plurality of lifting cylinders (19, 119) associated with a lower part of the platform (18) and at least one translation and oscillation actuator (20, 120; 32) comprising at least one translation cylinder (20, 120; 32) associated at a side of the platform (18), the lifting cylinders (19, 119) and the at least one translation cylinder (20, 120; 32) being for driving independently and together to obtain on the hearth (11) desired movements of lifting, translation, swinging, oscillation or a combination of such movements.   
     
     
       2. The device as in claim 1, wherein the translation and/or oscillation actuator comprises at least a horizontal translation cylinder (20, 120) with its axis of drive substantially parallel to the platform (18). 
     
     
       3. The device as in claim 1, wherein the translation and/or oscillation actuator comprises at least a connecting rod element (32) one end of which is anchored by one side to the platform (18). 
     
     
       4. The device as in claim 1, wherein the platform comprises means for releasably centering and clamping (25) the hearth (11) in relation to the platform (18). 
     
     
       5. An apparatus comprising the device, the hearth (11), the cooled side wall (12) and the closure system (14) as in claim 1, wherein between the cooled side wall (12) and the closure system (14) there is a sand joint (31) which can be temporarily disconnected. 
     
     
       6. The apparatus as in claim 5, wherein the area of contact between the side wall (12) and the closure system (14) is at least partly arched. 
     
     
       7. The device as in claim 1, wherein the hearth (11) has sliding means (24) in relation to the platform (18). 
     
     
       8. The device as in claim 1, wherein at least one member of the group consisting of at least one of said lifting cylinders (119) and at least one said translation cylinder (120) are a double opposed cylinder. 
     
     
       9. The device as in claim 1, which includes barrier-type protection means (27) at least for the lifting cylinders (19, 119). 
     
     
       10. The device as in claim 1, which includes clamping means (28) in the horizontal position of the platform (18). 
     
     
       11. The device as in claim 1, wherein the platform (18) includes anti-slip pads (29) cooperating with stationary side walls (30). 
     
     
       12. The device as in claim 1, wherein the platform (18) is of the elongated type (118) so as to cover at least one travel of horizontal translation "11" of the hearth (11) for loading operations, maintenance and/or replacement of the hearth (11) or parts thereof. 
     
     
       13. The device as in claim 1, wherein the platform (18) can be temporally associated with an adddition (218) to define an elongated platform (18) to support the hearth (11) in the horizontally translated position. 
     
     
       14. The device as in claim 1, which includes at least temporary support means (35) for the hearth (11) when it has been discharged from the platform (18), the support means being associated with moving means (34). 
     
     
       15. The device of claim 1, wherein the plurality of lifting cylinders suspend the platform in midair. 
     
     
       16. The device of claim 1, wherein said plurality of lifting cylinders is a plurality of substantially vertical lifting cylinders (19, 119), symmetrically disposed under said platform (18), each one of said vertical lifting cylinders (19, 119) having a first fixed end and a second end connected to said platform (18), and said at least one translation cylinder is at least one substantially horizontal actuator (20, 32, 120), having a first fixed end and a second end laterally connected to said platform (18), wherein the selected actuation of at least one of said vertical lifting cylinders (19, 119) in combination with the selected actuation of said horizontal actuator (20, 32, 120) causes the movement of said platform (18) and of the hearth (11) supported thereon by horizontally translating, vertically lifting, swinging on a longitudinal plane, oscillating on a transverse plane or any combination thereof. 
     
     
       17. The apparatus of claim 5, wherein the cooled sidewall swings with the hearth. 
     
     
       18. The apparatus of claim 5, wherein the hearth is selected from the group consisting of a channel hearth, an EBT hearth, and an OBT hearth. 
     
     
       19. The apparatus of claim 5, wherein the hearth is selected from the group consisting of a direct current hearth and an alternating current hearth.